X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=autorandr.py;h=e5ab42fdd0308695e720b6ada0415ccdd8751c0e;hb=b0257a2703e12139c14f524f502c1f27c99ae527;hp=18381df0fff950a2713030c4afe99bf3354c07ba;hpb=8e23d69d74eb0d60a7763901ceddbfa7851b861d;p=deb_pkgs%2Fautorandr.git

diff --git a/autorandr.py b/autorandr.py
index 18381df..e5ab42f 100755
--- a/autorandr.py
+++ b/autorandr.py
@@ -4,7 +4,7 @@
 # autorandr.py
 # Copyright (c) 2015, Phillip Berndt
 #
-# Experimental autorandr rewrite in Python
+# Autorandr rewrite in Python
 #
 # This script aims to be fully compatible with the original autorandr.
 #
@@ -23,23 +23,34 @@
 #
 
 from __future__ import print_function
-import copy
-import getopt
 
 import binascii
+import copy
+import getopt
 import hashlib
 import os
+import posix
+import pwd
 import re
 import subprocess
 import sys
-from distutils.version import LooseVersion as Version
+import shutil
+import time
 
-from itertools import chain
 from collections import OrderedDict
+from distutils.version import LooseVersion as Version
+from functools import reduce
+from itertools import chain
+
+try:
+    input = raw_input
+except NameError:
+    pass
 
 virtual_profiles = [
     # (name, description, callback)
     ("common", "Clone all connected outputs at the largest common resolution", None),
+    ("clone-largest", "Clone all connected outputs with the largest resolution (scaled down if necessary)", None),
     ("horizontal", "Stack all connected outputs horizontally at their largest resolution", None),
     ("vertical", "Stack all connected outputs vertically at their largest resolution", None),
 ]
@@ -50,14 +61,19 @@ Usage: autorandr [options]
 -h, --help              get this small help
 -c, --change            reload current setup
 -s, --save <profile>    save your current setup to profile <profile>
+-r, --remove <profile>  remove profile <profile>
 -l, --load <profile>    load profile <profile>
 -d, --default <profile> make profile <profile> the default profile
+--skip-options <option> comma separated list of xrandr arguments (e.g. "gamma")
+                        to skip both in detecting changes and applying a profile
 --force                 force (re)loading of a profile
 --fingerprint           fingerprint your current hardware setup
 --config                dump your current xrandr setup
 --dry-run               don't change anything, only print the xrandr commands
+--debug                 enable verbose output
+--batch                 run autorandr for all users with active X11 sessions
 
- To prevent a profile from being loaded, place a script call "block" in its
+ To prevent a profile from being loaded, place a script called "block" in its
  directory. The script is evaluated before the screen setup is inspected, and
  in case of it returning a value of 0 the profile is skipped. This can be used
  to query the status of a docking station you are about to leave.
@@ -66,13 +82,54 @@ Usage: autorandr [options]
  To change this behaviour and switch to a fallback configuration, specify
  --default <profile>.
 
- Another script called "postswitch "can be placed in the directory
- ~/.autorandr as well as in any profile directories: The scripts are executed
- after a mode switch has taken place and can notify window managers.
+ Another script called "postswitch" can be placed in the directory
+ ~/.config/autorandr (or ~/.autorandr if you have an old installation) as well
+ as in any profile directories: The scripts are executed after a mode switch
+ has taken place and can notify window managers.
 
  The following virtual configurations are available:
 """.strip()
 
+
+class AutorandrException(Exception):
+    def __init__(self, message, original_exception=None, report_bug=False):
+        self.message = message
+        self.report_bug = report_bug
+        if original_exception:
+            self.original_exception = original_exception
+            trace = sys.exc_info()[2]
+            while trace.tb_next:
+                trace = trace.tb_next
+            self.line = trace.tb_lineno
+            self.file_name = trace.tb_frame.f_code.co_filename
+        else:
+            try:
+                import inspect
+                frame = inspect.currentframe().f_back
+                self.line = frame.f_lineno
+                self.file_name = frame.f_code.co_filename
+            except:
+                self.line = None
+                self.file_name = None
+            self.original_exception = None
+
+        if os.path.abspath(self.file_name) == os.path.abspath(sys.argv[0]):
+            self.file_name = None
+
+    def __str__(self):
+        retval = [self.message]
+        if self.line:
+            retval.append(" (line %d%s)" % (self.line, ("; %s" % self.file_name) if self.file_name else ""))
+        if self.original_exception:
+            retval.append(":\n  ")
+            retval.append(str(self.original_exception).replace("\n", "\n  "))
+        if self.report_bug:
+            retval.append("\nThis appears to be a bug. Please help improving autorandr by reporting it upstream:"
+                          "\nhttps://github.com/phillipberndt/autorandr/issues"
+                          "\nPlease attach the output of `xrandr --verbose` to your bug report if appropriate.")
+        return "".join(retval)
+
+
 class XrandrOutput(object):
     "Represents an XRandR output"
 
@@ -82,37 +139,63 @@ class XrandrOutput(object):
         (?:                                                                             # Differentiate disconnected and connected in first line
             disconnected |
             unknown\ connection |
-            (?P<connected>connected)\s+                                                 # If connected:
-            (?P<primary>primary\ )?                                                     # Might be primary screen
+            (?P<connected>connected)
+        )
+        \s*
+        (?P<primary>primary\ )?                                                         # Might be primary screen
+        (?:\s*
             (?P<width>[0-9]+)x(?P<height>[0-9]+)                                        # Resolution (might be overridden below!)
-            \+(?P<x>[0-9]+)\+(?P<y>[0-9]+)\s+                                           # Position
+            \+(?P<x>-?[0-9]+)\+(?P<y>-?[0-9]+)\s+                                       # Position
             (?:\(0x[0-9a-fA-F]+\)\s+)?                                                  # XID
             (?P<rotate>(?:normal|left|right|inverted))\s+                               # Rotation
             (?:(?P<reflect>X\ and\ Y|X|Y)\ axis)?                                       # Reflection
-        ).*
+        )?                                                                              # .. but everything of the above only if the screen is in use.
+        (?:[\ \t]*\([^\)]+\))(?:\s*[0-9]+mm\sx\s[0-9]+mm)?
+        (?:[\ \t]*panning\ (?P<panning>[0-9]+x[0-9]+\+[0-9]+\+[0-9]+))?                 # Panning information
+        (?:[\ \t]*tracking\ (?P<tracking>[0-9]+x[0-9]+\+[0-9]+\+[0-9]+))?               # Tracking information
+        (?:[\ \t]*border\ (?P<border>(?:[0-9]+/){3}[0-9]+))?                            # Border information
         (?:\s*(?:                                                                       # Properties of the output
-            Gamma: (?P<gamma>[0-9\.:\s]+) |                                             # Gamma value
-            Transform: (?P<transform>[0-9\.\s]+) |                                      # Transformation matrix
-            EDID: (?P<edid>[0-9a-f\s]+) |                                               # EDID of the output
+            Gamma: (?P<gamma>(?:inf|[0-9\.: e])+) |                                     # Gamma value
+            Transform: (?P<transform>(?:[\-0-9\. ]+\s+){3}) |                           # Transformation matrix
+            EDID: (?P<edid>\s*?(?:\\n\\t\\t[0-9a-f]+)+) |                               # EDID of the output
             (?![0-9])[^:\s][^:\n]+:.*(?:\s\\t[\\t ].+)*                                 # Other properties
         ))+
         \s*
         (?P<modes>(?:
-            (?P<mode_width>[0-9]+)x(?P<mode_height>[0-9]+).+?\*current.+\s+
-                h:.+\s+v:.+clock\s+(?P<rate>[0-9\.]+)Hz\s* |                            # Interesting (current) resolution: Extract rate
-            [0-9]+x[0-9]+.+\s+h:.+\s+v:.+\s*                                            # Other resolutions
+            (?P<mode_name>\S+).+?\*current.*\s+                                         # Interesting (current) resolution: Extract rate
+             h:\s+width\s+(?P<mode_width>[0-9]+).+\s+
+             v:\s+height\s+(?P<mode_height>[0-9]+).+clock\s+(?P<rate>[0-9\.]+)Hz\s* |
+            \S+(?:(?!\*current).)+\s+h:.+\s+v:.+\s*                                     # Other resolutions
         )*)
     """
 
     XRANDR_OUTPUT_MODES_REGEXP = """(?x)
-        (?P<width>[0-9]+)x(?P<height>[0-9]+)
-        .*?(?P<preferred>\+preferred)?
-        \s+h:.+
-        \s+v:.+clock\s+(?P<rate>[0-9\.]+)Hz
+        (?P<name>\S+).+?(?P<preferred>\+preferred)?\s+
+         h:\s+width\s+(?P<width>[0-9]+).+\s+
+         v:\s+height\s+(?P<height>[0-9]+).+clock\s+(?P<rate>[0-9\.]+)Hz\s* |
     """
 
+    XRANDR_13_DEFAULTS = {
+        "transform": "1,0,0,0,1,0,0,0,1",
+        "panning": "0x0",
+    }
+
+    XRANDR_12_DEFAULTS = {
+        "reflect": "normal",
+        "rotate": "normal",
+        "gamma": "1.0:1.0:1.0",
+    }
+
+    XRANDR_DEFAULTS = dict(list(XRANDR_13_DEFAULTS.items()) + list(XRANDR_12_DEFAULTS.items()))
+
+    EDID_UNAVAILABLE = "--CONNECTED-BUT-EDID-UNAVAILABLE-"
+
     def __repr__(self):
-        return "<%s%s %s>" % (self.output, (" %s..%s" % (self.edid[:5], self.edid[-5:])) if self.edid else "", " ".join(self.option_vector))
+        return "<%s%s %s>" % (self.output, self.short_edid, " ".join(self.option_vector))
+
+    @property
+    def short_edid(self):
+        return ("%s..%s" % (self.edid[:5], self.edid[-5:])) if self.edid else ""
 
     @property
     def options_with_defaults(self):
@@ -121,32 +204,33 @@ class XrandrOutput(object):
             return self.options
         options = {}
         if xrandr_version() >= Version("1.3"):
-            options.update({
-                "transform": "1,0,0,0,1,0,0,0,1",
-            })
+            options.update(self.XRANDR_13_DEFAULTS)
         if xrandr_version() >= Version("1.2"):
-            options.update({
-                "reflect": "normal",
-                "rotate": "normal",
-                "gamma": "1:1:1",
-            })
+            options.update(self.XRANDR_12_DEFAULTS)
         options.update(self.options)
-        return options
+        return {a: b for a, b in options.items() if a not in self.ignored_options}
+
+    @property
+    def filtered_options(self):
+        "Return a dictionary of options without ignored options"
+        return {a: b for a, b in self.options.items() if a not in self.ignored_options}
 
     @property
     def option_vector(self):
         "Return the command line parameters for XRandR for this instance"
-        return sum([["--%s" % option[0], option[1]] if option[1] else ["--%s" % option[0]] for option in chain((("output", self.output),), self.options_with_defaults.items())], [])
+        return sum([["--%s" % option[0], option[1]] if option[1] else ["--%s" % option[0]] for option in chain((("output", self.output),), sorted(self.options_with_defaults.items()))], [])
 
     @property
     def option_string(self):
         "Return the command line parameters in the configuration file format"
-        return "\n".join([ " ".join(option) if option[1] else option[0] for option in chain((("output", self.output),), self.options.items())])
+        return "\n".join([" ".join(option) if option[1] else option[0] for option in chain((("output", self.output),), sorted(self.filtered_options.items()))])
 
     @property
     def sort_key(self):
         "Return a key to sort the outputs for xrandr invocation"
         if not self.edid:
+            return -2
+        if "off" in self.options:
             return -1
         if "pos" in self.options:
             x, y = map(float, self.options["pos"].split("x"))
@@ -159,6 +243,21 @@ class XrandrOutput(object):
         self.output = output
         self.edid = edid
         self.options = options
+        self.ignored_options = []
+        self.remove_default_option_values()
+
+    def set_ignored_options(self, options):
+        "Set a list of xrandr options that are never used (neither when comparing configurations nor when applying them)"
+        self.ignored_options = list(options)
+
+    def remove_default_option_values(self):
+        "Remove values from the options dictionary that are superflous"
+        if "off" in self.options and len(self.options.keys()) > 1:
+            self.options = {"off": None}
+            return
+        for option, default_value in self.XRANDR_DEFAULTS.items():
+            if option in self.options and self.options[option] == default_value:
+                del self.options[option]
 
     @classmethod
     def from_xrandr_output(cls, xrandr_output):
@@ -167,63 +266,78 @@ class XrandrOutput(object):
         This method also returns a list of modes supported by the output.
         """
         try:
+            xrandr_output = xrandr_output.replace("\r\n", "\n")
             match_object = re.search(XrandrOutput.XRANDR_OUTPUT_REGEXP, xrandr_output)
         except:
-            raise RuntimeError("Parsing XRandR output failed, there is an error in the regular expression.")
+            raise AutorandrException("Parsing XRandR output failed, there is an error in the regular expression.", report_bug=True)
         if not match_object:
             debug = debug_regexp(XrandrOutput.XRANDR_OUTPUT_REGEXP, xrandr_output)
-            raise RuntimeError("Parsing XRandR output failed, the regular expression did not match: %s" % debug)
+            raise AutorandrException("Parsing XRandR output failed, the regular expression did not match: %s" % debug, report_bug=True)
         remainder = xrandr_output[len(match_object.group(0)):]
         if remainder:
-            raise RuntimeError(("Parsing XRandR output failed, %d bytes left unmatched after regular expression,"
-                                "starting with ..'%s'.") % (len(remainder), remainder[:10]))
-
+            raise AutorandrException(("Parsing XRandR output failed, %d bytes left unmatched after regular expression, "
+                                      "starting at byte %d with ..'%s'.") % (len(remainder), len(match_object.group(0)), remainder[:10]), report_bug=True)
 
         match = match_object.groupdict()
 
         modes = []
         if match["modes"]:
-            modes = [ x.groupdict() for x in re.finditer(XrandrOutput.XRANDR_OUTPUT_MODES_REGEXP, match["modes"]) ]
+            modes = [x.groupdict() for x in re.finditer(XrandrOutput.XRANDR_OUTPUT_MODES_REGEXP, match["modes"]) if x.group("name")]
             if not modes:
-                raise RuntimeError("Parsing XRandR output failed, couldn't find any display modes")
+                raise AutorandrException("Parsing XRandR output failed, couldn't find any display modes", report_bug=True)
 
         options = {}
         if not match["connected"]:
-            options["off"] = None
             edid = None
         else:
-            if "mode_width" in match:
+            edid = "".join(match["edid"].strip().split()) if match["edid"] else "%s-%s" % (XrandrOutput.EDID_UNAVAILABLE, match["output"])
+
+        if not match["width"]:
+            options["off"] = None
+        else:
+            if match["mode_name"]:
+                options["mode"] = match["mode_name"]
+            elif match["mode_width"]:
                 options["mode"] = "%sx%s" % (match["mode_width"], match["mode_height"])
             else:
                 if match["rotate"] not in ("left", "right"):
                     options["mode"] = "%sx%s" % (match["width"], match["height"])
                 else:
                     options["mode"] = "%sx%s" % (match["height"], match["width"])
-            if match["rotate"] != "normal":
-                options["rotate"] = match["rotate"]
-            if "reflect" in match:
-                if match["reflect"] == "X":
-                    options["reflect"] = "x"
-                elif match["reflect"] == "Y":
-                    options["reflect"] = "y"
-                elif match["reflect"] == "X and Y":
-                    options["reflect"] = "xy"
+            options["rotate"] = match["rotate"]
+            if match["primary"]:
+                options["primary"] = None
+            if match["reflect"] == "X":
+                options["reflect"] = "x"
+            elif match["reflect"] == "Y":
+                options["reflect"] = "y"
+            elif match["reflect"] == "X and Y":
+                options["reflect"] = "xy"
             options["pos"] = "%sx%s" % (match["x"], match["y"])
+            if match["panning"]:
+                panning = [match["panning"]]
+                if match["tracking"]:
+                    panning += ["/", match["tracking"]]
+                    if match["border"]:
+                        panning += ["/", match["border"]]
+                options["panning"] = "".join(panning)
             if match["transform"]:
                 transformation = ",".join(match["transform"].strip().split())
                 if transformation != "1.000000,0.000000,0.000000,0.000000,1.000000,0.000000,0.000000,0.000000,1.000000":
                     options["transform"] = transformation
-                    if "mode_width" not in match:
+                    if not match["mode_name"]:
                         # TODO We'd need to apply the reverse transformation here. Let's see if someone complains, I doubt that this
                         # special case is actually required.
-                        print("Warning: Output %s has a transformation applied. Could not determine correct mode!", file=sys.stderr)
+                        print("Warning: Output %s has a transformation applied. Could not determine correct mode! Using `%s'." % (match["output"], options["mode"]), file=sys.stderr)
             if match["gamma"]:
                 gamma = match["gamma"].strip()
-                if gamma != "1.0:1.0:1.0":
-                    options["gamma"] = gamma
+                # xrandr prints different values in --verbose than it accepts as a parameter value for --gamma
+                # Also, it is not able to work with non-standard gamma ramps. Finally, it auto-corrects 0 to 1,
+                # so we approximate by 1e-10.
+                gamma = ":".join([str(max(1e-10, round(1. / float(x), 3))) for x in gamma.split(":")])
+                options["gamma"] = gamma
             if match["rate"]:
                 options["rate"] = match["rate"]
-            edid = "".join(match["edid"].strip().split())
 
         return XrandrOutput(match["output"], edid, options), modes
 
@@ -234,18 +348,22 @@ class XrandrOutput(object):
         for line in configuration.split("\n"):
             if line:
                 line = line.split(None, 1)
+                if line and line[0].startswith("#"):
+                    continue
                 options[line[0]] = line[1] if len(line) > 1 else None
-        if "off" in options:
-            edid = None
+
+        edid = None
+
+        if options["output"] in edid_map:
+            edid = edid_map[options["output"]]
         else:
-            if options["output"] in edid_map:
-                edid = edid_map[options["output"]]
-            else:
-                fuzzy_edid_map = [ re.sub("(card[0-9]+|-)", "", x) for x in edid_map.keys() ]
-                fuzzy_output = re.sub("(card[0-9]+|-)", "", options["output"])
-                if fuzzy_output not in fuzzy_edid_map:
-                    raise RuntimeError("Failed to find a corresponding output in config/setup for output `%s'" % options["output"])
+            # This fuzzy matching is for legacy autorandr that used sysfs output names
+            fuzzy_edid_map = [re.sub("(card[0-9]+|-)", "", x) for x in edid_map.keys()]
+            fuzzy_output = re.sub("(card[0-9]+|-)", "", options["output"])
+            if fuzzy_output in fuzzy_edid_map:
                 edid = edid_map[list(edid_map.keys())[fuzzy_edid_map.index(fuzzy_output)]]
+            elif "off" not in options:
+                raise AutorandrException("Failed to find an EDID for output `%s' in setup file, required as `%s' is not off in config file." % (options["output"], options["output"]))
         output = options["output"]
         del options["output"]
 
@@ -254,28 +372,58 @@ class XrandrOutput(object):
     def edid_equals(self, other):
         "Compare to another XrandrOutput's edid and on/off-state, taking legacy autorandr behaviour (md5sum'ing) into account"
         if self.edid and other.edid:
-            if len(self.edid) == 32 and len(other.edid) != 32:
+            if len(self.edid) == 32 and len(other.edid) != 32 and not other.edid.startswith(XrandrOutput.EDID_UNAVAILABLE):
                 return hashlib.md5(binascii.unhexlify(other.edid)).hexdigest() == self.edid
-            if len(self.edid) != 32 and len(other.edid) == 32:
+            if len(self.edid) != 32 and len(other.edid) == 32 and not self.edid.startswith(XrandrOutput.EDID_UNAVAILABLE):
                 return hashlib.md5(binascii.unhexlify(self.edid)).hexdigest() == other.edid
         return self.edid == other.edid
 
+    def __ne__(self, other):
+        return not (self == other)
+
     def __eq__(self, other):
-        return self.edid == other.edid and self.output == other.output and self.options == other.options
+        return self.edid_equals(other) and self.output == other.output and self.filtered_options == other.filtered_options
+
+    def verbose_diff(self, other):
+        "Compare to another XrandrOutput and return a list of human readable differences"
+        diffs = []
+        if not self.edid_equals(other):
+            diffs.append("EDID `%s' differs from `%s'" % (self.short_edid, other.short_edid))
+        if self.output != other.output:
+            diffs.append("Output name `%s' differs from `%s'" % (self.output, other.output))
+        if "off" in self.options and "off" not in other.options:
+            diffs.append("The output is disabled currently, but active in the new configuration")
+        elif "off" in other.options and "off" not in self.options:
+            diffs.append("The output is currently enabled, but inactive in the new configuration")
+        else:
+            for name in set(chain.from_iterable((self.options.keys(), other.options.keys()))):
+                if name not in other.options:
+                    diffs.append("Option --%s %sis not present in the new configuration" % (name, "(= `%s') " % self.options[name] if self.options[name] else ""))
+                elif name not in self.options:
+                    diffs.append("Option --%s (`%s' in the new configuration) is not present currently" % (name, other.options[name]))
+                elif self.options[name] != other.options[name]:
+                    diffs.append("Option --%s %sis `%s' in the new configuration" % (name, "(= `%s') " % self.options[name] if self.options[name] else "", other.options[name]))
+        return diffs
+
 
 def xrandr_version():
     "Return the version of XRandR that this system uses"
     if getattr(xrandr_version, "version", False) is False:
         version_string = os.popen("xrandr -v").read()
-        version = re.search("xrandr program version\s+([0-9\.]+)", version_string).group(1)
-        xrandr_version.version = Version(version)
+        try:
+            version = re.search("xrandr program version\s+([0-9\.]+)", version_string).group(1)
+            xrandr_version.version = Version(version)
+        except AttributeError:
+            xrandr_version.version = Version("1.3.0")
+
     return xrandr_version.version
 
+
 def debug_regexp(pattern, string):
     "Use the partial matching functionality of the regex module to display debug info on a non-matching regular expression"
     try:
         import regex
-        bounds = ( 0, len(string) )
+        bounds = (0, len(string))
         while bounds[0] != bounds[1]:
             half = int((bounds[0] + bounds[1]) / 2)
             if half == bounds[0]:
@@ -283,84 +431,107 @@ def debug_regexp(pattern, string):
             bounds = (half, bounds[1]) if regex.search(pattern, string[:half], partial=True) else (bounds[0], half - 1)
         partial_length = bounds[0]
         return ("Regular expression matched until position "
-              "%d, ..'%s', and did not match from '%s'.." % (partial_length, string[max(0, partial_length-20):partial_length],
-                                                             string[partial_length:partial_length+10]))
+                "%d, ..'%s', and did not match from '%s'.." % (partial_length, string[max(0, partial_length - 20):partial_length],
+                                                               string[partial_length:partial_length + 10]))
     except ImportError:
         pass
-    return "Debug information available if `regex' module is installed."
+    return "Debug information would be available if the `regex' module was installed."
+
 
 def parse_xrandr_output():
     "Parse the output of `xrandr --verbose' into a list of outputs"
     xrandr_output = os.popen("xrandr -q --verbose").read()
     if not xrandr_output:
-        raise RuntimeError("Failed to run xrandr")
+        raise AutorandrException("Failed to run xrandr")
 
     # We are not interested in screens
     xrandr_output = re.sub("(?m)^Screen [0-9].+", "", xrandr_output).strip()
 
     # Split at output boundaries and instanciate an XrandrOutput per output
     split_xrandr_output = re.split("(?m)^([^ ]+ (?:(?:dis)?connected|unknown connection).*)$", xrandr_output)
+    if len(split_xrandr_output) < 2:
+        raise AutorandrException("No output boundaries found", report_bug=True)
     outputs = OrderedDict()
     modes = OrderedDict()
     for i in range(1, len(split_xrandr_output), 2):
         output_name = split_xrandr_output[i].split()[0]
-        output, output_modes = XrandrOutput.from_xrandr_output("".join(split_xrandr_output[i:i+2]))
+        output, output_modes = XrandrOutput.from_xrandr_output("".join(split_xrandr_output[i:i + 2]))
         outputs[output_name] = output
         if output_modes:
             modes[output_name] = output_modes
 
     return outputs, modes
 
+
 def load_profiles(profile_path):
     "Load the stored profiles"
 
     profiles = {}
     for profile in os.listdir(profile_path):
         config_name = os.path.join(profile_path, profile, "config")
-        setup_name  = os.path.join(profile_path, profile, "setup")
+        setup_name = os.path.join(profile_path, profile, "setup")
         if not os.path.isfile(config_name) or not os.path.isfile(setup_name):
             continue
 
-        edids = dict([ x.strip().split() for x in open(setup_name).readlines() ])
+        edids = dict([x.split() for x in (y.strip() for y in open(setup_name).readlines()) if x and x[0] != "#"])
 
         config = {}
         buffer = []
         for line in chain(open(config_name).readlines(), ["output"]):
             if line[:6] == "output" and buffer:
                 config[buffer[0].strip().split()[-1]] = XrandrOutput.from_config_file(edids, "".join(buffer))
-                buffer = [ line ]
+                buffer = [line]
             else:
                 buffer.append(line)
 
         for output_name in list(config.keys()):
-            if "off" in config[output_name].options:
+            if config[output_name].edid is None:
                 del config[output_name]
 
-        profiles[profile] = config
+        profiles[profile] = {"config": config, "path": os.path.join(profile_path, profile), "config-mtime": os.stat(config_name).st_mtime}
 
     return profiles
 
-def find_profile(current_config, profiles):
-    "Find a profile matching the currently connected outputs"
+
+def get_symlinks(profile_path):
+    "Load all symlinks from a directory"
+
+    symlinks = {}
+    for link in os.listdir(profile_path):
+        file_name = os.path.join(profile_path, link)
+        if os.path.islink(file_name):
+            symlinks[link] = os.readlink(file_name)
+
+    return symlinks
+
+
+def find_profiles(current_config, profiles):
+    "Find profiles matching the currently connected outputs"
+    detected_profiles = []
     for profile_name, profile in profiles.items():
+        config = profile["config"]
         matches = True
-        for name, output in profile.items():
+        for name, output in config.items():
             if not output.edid:
                 continue
             if name not in current_config or not output.edid_equals(current_config[name]):
                 matches = False
                 break
-        if not matches or any(( name not in profile.keys() for name in current_config.keys() if current_config[name].edid )):
+        if not matches or any((name not in config.keys() for name in current_config.keys() if current_config[name].edid)):
             continue
         if matches:
-            return profile_name
+            detected_profiles.append(profile_name)
+    return detected_profiles
+
+
+def profile_blocked(profile_path, meta_information=None):
+    """Check if a profile is blocked.
+
+    meta_information is expected to be an dictionary. It will be passed to the block scripts
+    in the environment, as variables called AUTORANDR_<CAPITALIZED_KEY_HERE>.
+    """
+    return not exec_scripts(profile_path, "block", meta_information)
 
-def profile_blocked(profile_path):
-    "Check if a profile is blocked"
-    script = os.path.join(profile_path, "blocked")
-    if not os.access(script, os.X_OK | os.F_OK):
-        return False
-    return subprocess.call(script) == 0
 
 def output_configuration(configuration, config):
     "Write a configuration file"
@@ -368,6 +539,7 @@ def output_configuration(configuration, config):
     for output in outputs:
         print(configuration[output].option_string, file=config)
 
+
 def output_setup(configuration, setup):
     "Write a setup (fingerprint) file"
     outputs = sorted(configuration.keys())
@@ -375,6 +547,7 @@ def output_setup(configuration, setup):
         if configuration[output].edid:
             print(output, configuration[output].edid, file=setup)
 
+
 def save_configuration(profile_path, configuration):
     "Save a configuration into a profile"
     if not os.path.isdir(profile_path):
@@ -384,47 +557,162 @@ def save_configuration(profile_path, configuration):
     with open(os.path.join(profile_path, "setup"), "w") as setup:
         output_setup(configuration, setup)
 
-def apply_configuration(configuration, dry_run=False):
+
+def update_mtime(filename):
+    "Update a file's mtime"
+    try:
+        os.utime(filename, None)
+        return True
+    except:
+        return False
+
+
+def call_and_retry(*args, **kwargs):
+    """Wrapper around subprocess.call that retries failed calls.
+
+    This function calls subprocess.call and on non-zero exit states,
+    waits a second and then retries once. This mitigates #47,
+    a timing issue with some drivers.
+    """
+    if "dry_run" in kwargs:
+        dry_run = kwargs["dry_run"]
+        del kwargs["dry_run"]
+    else:
+        dry_run = False
+    kwargs_redirected = dict(kwargs)
+    if not dry_run:
+        if hasattr(subprocess, "DEVNULL"):
+            kwargs_redirected["stdout"] = getattr(subprocess, "DEVNULL")
+        else:
+            kwargs_redirected["stdout"] = open(os.devnull, "w")
+        kwargs_redirected["stderr"] = kwargs_redirected["stdout"]
+    retval = subprocess.call(*args, **kwargs_redirected)
+    if retval != 0:
+        time.sleep(1)
+        retval = subprocess.call(*args, **kwargs)
+    return retval
+
+
+def apply_configuration(new_configuration, current_configuration, dry_run=False):
     "Apply a configuration"
-    outputs = sorted(configuration.keys(), key=lambda x: configuration[x].sort_key)
+    outputs = sorted(new_configuration.keys(), key=lambda x: new_configuration[x].sort_key)
     if dry_run:
-        base_argv = [ "echo", "xrandr" ]
+        base_argv = ["echo", "xrandr"]
     else:
-        base_argv = [ "xrandr" ]
-
-    # Disable all unused outputs
-    argv = base_argv[:]
+        base_argv = ["xrandr"]
+
+    # There are several xrandr / driver bugs we need to take care of here:
+    # - We cannot enable more than two screens at the same time
+    #   See https://github.com/phillipberndt/autorandr/pull/6
+    #   and commits f4cce4d and 8429886.
+    # - We cannot disable all screens
+    #   See https://github.com/phillipberndt/autorandr/pull/20
+    # - We should disable screens before enabling others, because there's
+    #   a limit on the number of enabled screens
+    # - We must make sure that the screen at 0x0 is activated first,
+    #   or the other (first) screen to be activated would be moved there.
+    # - If an active screen already has a transformation and remains active,
+    #   the xrandr call fails with an invalid RRSetScreenSize parameter error.
+    #   Update the configuration in 3 passes in that case.  (On Haswell graphics,
+    #   at least.)
+    # - Some implementations can not handle --transform at all, so avoid it unless
+    #   necessary. (See https://github.com/phillipberndt/autorandr/issues/37)
+    # - Some implementations can not handle --panning without specifying --fb
+    #   explicitly, so avoid it unless necessary.
+    #   (See https://github.com/phillipberndt/autorandr/issues/72)
+
+    auxiliary_changes_pre = []
+    disable_outputs = []
+    enable_outputs = []
+    remain_active_count = 0
     for output in outputs:
-        if not configuration[output].edid:
-            argv += configuration[output].option_vector
-    if argv != base_argv:
-        if subprocess.call(argv) != 0:
+        if not new_configuration[output].edid or "off" in new_configuration[output].options:
+            disable_outputs.append(new_configuration[output].option_vector)
+        else:
+            if "off" not in current_configuration[output].options:
+                remain_active_count += 1
+
+            option_vector = new_configuration[output].option_vector
+            if xrandr_version() >= Version("1.3.0"):
+                for option in ("transform", "panning"):
+                    if option in current_configuration[output].options:
+                        auxiliary_changes_pre.append(["--output", output, "--%s" % option, "none"])
+                    else:
+                        try:
+                            option_index = option_vector.index("--%s" % option)
+                            if option_vector[option_index + 1] == XrandrOutput.XRANDR_DEFAULTS[option]:
+                                option_vector = option_vector[:option_index] + option_vector[option_index + 2:]
+                        except ValueError:
+                            pass
+
+            enable_outputs.append(option_vector)
+
+    # Perform pe-change auxiliary changes
+    if auxiliary_changes_pre:
+        argv = base_argv + list(chain.from_iterable(auxiliary_changes_pre))
+        if call_and_retry(argv, dry_run=dry_run) != 0:
+            raise AutorandrException("Command failed: %s" % " ".join(argv))
+
+    # Disable unused outputs, but make sure that there always is at least one active screen
+    disable_keep = 0 if remain_active_count else 1
+    if len(disable_outputs) > disable_keep:
+        if call_and_retry(base_argv + list(chain.from_iterable(disable_outputs[:-1] if disable_keep else disable_outputs)), dry_run=dry_run) != 0:
+            # Disabling the outputs failed. Retry with the next command:
+            # Sometimes disabling of outputs fails due to an invalid RRSetScreenSize.
+            # This does not occur if simultaneously the primary screen is reset.
+            pass
+        else:
+            disable_outputs = disable_outputs[-1:] if disable_keep else []
+
+    # If disable_outputs still has more than one output in it, one of the xrandr-calls below would
+    # disable the last two screens. This is a problem, so if this would happen, instead disable only
+    # one screen in the first call below.
+    if len(disable_outputs) > 0 and len(disable_outputs) % 2 == 0:
+        # In the context of a xrandr call that changes the display state, `--query' should do nothing
+        disable_outputs.insert(0, ['--query'])
+
+    # Enable the remaining outputs in pairs of two operations
+    operations = disable_outputs + enable_outputs
+    for index in range(0, len(operations), 2):
+        argv = base_argv + list(chain.from_iterable(operations[index:index + 2]))
+        if call_and_retry(argv, dry_run=dry_run) != 0:
+            raise AutorandrException("Command failed: %s" % " ".join(argv))
+
+
+def is_equal_configuration(source_configuration, target_configuration):
+    "Check if all outputs from target are already configured correctly in source"
+    for output in target_configuration.keys():
+        if (output not in source_configuration) or (source_configuration[output] != target_configuration[output]):
             return False
+    return True
 
-    # Enable remaining outputs in pairs of two
-    remaining_outputs = [ x for x in outputs if configuration[x].edid ]
-    for index in range(0, len(remaining_outputs), 2):
-        if subprocess.call((base_argv[:] + configuration[remaining_outputs[index]].option_vector + (configuration[remaining_outputs[index + 1]].option_vector if index < len(remaining_outputs) - 1 else []))) != 0:
-            return False
 
 def add_unused_outputs(source_configuration, target_configuration):
     "Add outputs that are missing in target to target, in 'off' state"
     for output_name, output in source_configuration.items():
         if output_name not in target_configuration:
-            target_configuration[output_name] = XrandrOutput(output_name, output.edid, { "off": None })
+            target_configuration[output_name] = XrandrOutput(output_name, output.edid, {"off": None})
+
+
+def remove_irrelevant_outputs(source_configuration, target_configuration):
+    "Remove outputs from target that ought to be 'off' and already are"
+    for output_name, output in source_configuration.items():
+        if "off" in output.options and output_name in target_configuration and "off" in target_configuration[output_name].options:
+            del target_configuration[output_name]
+
 
 def generate_virtual_profile(configuration, modes, profile_name):
     "Generate one of the virtual profiles"
     configuration = copy.deepcopy(configuration)
     if profile_name == "common":
-        common_resolution = [ set(( ( mode["width"], mode["height"] ) for mode in output )) for output in modes.values() ]
+        common_resolution = [set(((mode["width"], mode["height"]) for mode in output_modes)) for output, output_modes in modes.items() if configuration[output].edid]
         common_resolution = reduce(lambda a, b: a & b, common_resolution[1:], common_resolution[0])
-        common_resolution = sorted(common_resolution, key=lambda a: int(a[0])*int(a[1]))
+        common_resolution = sorted(common_resolution, key=lambda a: int(a[0]) * int(a[1]))
         if common_resolution:
             for output in configuration:
                 configuration[output].options = {}
-                if output in modes:
-                    configuration[output].options["mode"] = "%sx%s" % common_resolution[-1]
+                if output in modes and configuration[output].edid:
+                    configuration[output].options["mode"] = [x["name"] for x in sorted(modes[output], key=lambda x: 0 if x["preferred"] else 1) if x["width"] == common_resolution[-1][0] and x["height"] == common_resolution[-1][1]][0]
                     configuration[output].options["pos"] = "0x0"
                 else:
                     configuration[output].options["off"] = None
@@ -439,49 +727,286 @@ def generate_virtual_profile(configuration, modes, profile_name):
 
         for output in configuration:
             configuration[output].options = {}
-            if output in modes:
-                mode = sorted(modes[output], key=lambda a: int(a["width"])*int(a["height"]) + (10**6 if a["preferred"] else 0))[-1]
-                configuration[output].options["mode"] = "%sx%s" % (mode["width"], mode["height"])
+            if output in modes and configuration[output].edid:
+                mode = sorted(modes[output], key=lambda a: int(a["width"]) * int(a["height"]) + (10**6 if a["preferred"] else 0))[-1]
+                configuration[output].options["mode"] = mode["name"]
                 configuration[output].options["rate"] = mode["rate"]
                 configuration[output].options["pos"] = pos_specifier % shift
                 shift += int(mode[shift_index])
             else:
                 configuration[output].options["off"] = None
+    elif profile_name == "clone-largest":
+        biggest_resolution = sorted([output_modes[0] for output, output_modes in modes.items()], key=lambda x: int(x["width"]) * int(x["height"]), reverse=True)[0]
+        for output in configuration:
+            configuration[output].options = {}
+            if output in modes and configuration[output].edid:
+                mode = sorted(modes[output], key=lambda a: int(a["width"]) * int(a["height"]) + (10**6 if a["preferred"] else 0))[-1]
+                configuration[output].options["mode"] = mode["name"]
+                configuration[output].options["rate"] = mode["rate"]
+                configuration[output].options["pos"] = "0x0"
+                scale = max(float(biggest_resolution["width"]) / float(mode["width"]), float(biggest_resolution["height"]) / float(mode["height"]))
+                mov_x = (float(mode["width"]) * scale - float(biggest_resolution["width"])) / -2
+                mov_y = (float(mode["height"]) * scale - float(biggest_resolution["height"])) / -2
+                configuration[output].options["transform"] = "{},0,{},0,{},{},0,0,1".format(scale, mov_x, scale, mov_y)
+            else:
+                configuration[output].options["off"] = None
     return configuration
 
+
+def print_profile_differences(one, another):
+    "Print the differences between two profiles for debugging"
+    if one == another:
+        return
+    print("| Differences between the two profiles:", file=sys.stderr)
+    for output in set(chain.from_iterable((one.keys(), another.keys()))):
+        if output not in one:
+            if "off" not in another[output].options:
+                print("| Output `%s' is missing from the active configuration" % output, file=sys.stderr)
+        elif output not in another:
+            if "off" not in one[output].options:
+                print("| Output `%s' is missing from the new configuration" % output, file=sys.stderr)
+        else:
+            for line in one[output].verbose_diff(another[output]):
+                print("| [Output %s] %s" % (output, line), file=sys.stderr)
+    print("\\-", file=sys.stderr)
+
+
 def exit_help():
     "Print help and exit"
     print(help_text)
     for profile in virtual_profiles:
-        print("  %-10s %s" % profile[:2])
+        name, description = profile[:2]
+        description = [description]
+        max_width = 78 - 18
+        while len(description[0]) > max_width + 1:
+            left_over = description[0][max_width:]
+            description[0] = description[0][:max_width] + "-"
+            description.insert(1, "  %-15s %s" % ("", left_over))
+        description = "\n".join(description)
+        print("  %-15s %s" % (name, description))
     sys.exit(0)
 
-def exec_scripts(profile_path, script_name):
-    "Run userscripts"
-    for script in (os.path.join(profile_path, script_name), os.path.join(os.path.dirname(profile_path), script_name)):
-        if os.access(script, os.X_OK | os.F_OK):
-            subprocess.call(script)
+
+def exec_scripts(profile_path, script_name, meta_information=None):
+    """"Run userscripts
+
+    This will run all executables from the profile folder, and global per-user
+    and system-wide configuration folders, named script_name or residing in
+    subdirectories named script_name.d.
+
+    If profile_path is None, only global scripts will be invoked.
+
+    meta_information is expected to be an dictionary. It will be passed to the block scripts
+    in the environment, as variables called AUTORANDR_<CAPITALIZED_KEY_HERE>.
+
+    Returns True unless any of the scripts exited with non-zero exit status.
+    """
+    all_ok = True
+    if meta_information:
+        env = os.environ.copy()
+        env.update({"AUTORANDR_%s" % str(key).upper(): str(value) for (key, value) in meta_information.items()})
+    else:
+        env = os.environ.copy()
+
+    # If there are multiple candidates, the XDG spec tells to only use the first one.
+    ran_scripts = set()
+
+    user_profile_path = os.path.expanduser("~/.autorandr")
+    if not os.path.isdir(user_profile_path):
+        user_profile_path = os.path.join(os.environ.get("XDG_CONFIG_HOME", os.path.expanduser("~/.config")), "autorandr")
+
+    candidate_directories = chain((user_profile_path,), (os.path.join(x, "autorandr") for x in os.environ.get("XDG_CONFIG_DIRS", "/etc/xdg").split(":")))
+    if profile_path:
+        candidate_directories = chain((profile_path,), candidate_directories)
+
+    for folder in candidate_directories:
+
+        if script_name not in ran_scripts:
+            script = os.path.join(folder, script_name)
+            if os.access(script, os.X_OK | os.F_OK):
+                try:
+                    all_ok &= subprocess.call(script, env=env) != 0
+                except:
+                    raise AutorandrException("Failed to execute user command: %s" % (script,))
+                ran_scripts.add(script_name)
+
+        script_folder = os.path.join(folder, "%s.d" % script_name)
+        if os.access(script_folder, os.R_OK | os.X_OK) and os.path.isdir(script_folder):
+            for file_name in os.listdir(script_folder):
+                check_name = "d/%s" % (file_name,)
+                if check_name not in ran_scripts:
+                    script = os.path.join(script_folder, file_name)
+                    if os.access(script, os.X_OK | os.F_OK):
+                        try:
+                            all_ok &= subprocess.call(script, env=env) != 0
+                        except:
+                            raise AutorandrException("Failed to execute user command: %s" % (script,))
+                        ran_scripts.add(check_name)
+
+    return all_ok
+
+
+def dispatch_call_to_sessions(argv):
+    """Invoke autorandr for each open local X11 session with the given options.
+
+    The function iterates over all processes not owned by root and checks
+    whether they have DISPLAY and XAUTHORITY variables set. It strips the
+    screen from any variable it finds (i.e. :0.0 becomes :0) and checks whether
+    this display has been handled already. If it has not, it forks, changes
+    uid/gid to the user owning the process, reuses the process's environment
+    and runs autorandr with the parameters from argv.
+
+    This function requires root permissions. It only works for X11 servers that
+    have at least one non-root process running. It is susceptible for attacks
+    where one user runs a process with another user's DISPLAY variable - in
+    this case, it might happen that autorandr is invoked for the other user,
+    which won't work. Since no other harm than prevention of automated
+    execution of autorandr can be done this way, the assumption is that in this
+    situation, the local administrator will handle the situation."""
+
+    X11_displays_done = set()
+
+    autorandr_binary = os.path.abspath(argv[0])
+    backup_candidates = {}
+
+    def fork_child_autorandr(pwent, process_environ):
+        print("Running autorandr as %s for display %s" % (pwent.pw_name, process_environ["DISPLAY"]))
+        child_pid = os.fork()
+        if child_pid == 0:
+            # This will throw an exception if any of the privilege changes fails,
+            # so it should be safe. Also, note that since the environment
+            # is taken from a process owned by the user, reusing it should
+            # not leak any information.
+            os.setgroups([])
+            os.setresgid(pwent.pw_gid, pwent.pw_gid, pwent.pw_gid)
+            os.setresuid(pwent.pw_uid, pwent.pw_uid, pwent.pw_uid)
+            os.chdir(pwent.pw_dir)
+            os.environ.clear()
+            os.environ.update(process_environ)
+            os.execl(autorandr_binary, autorandr_binary, *argv[1:])
+            os.exit(1)
+        os.waitpid(child_pid, 0)
+
+    for directory in os.listdir("/proc"):
+        directory = os.path.join("/proc/", directory)
+        if not os.path.isdir(directory):
+            continue
+        environ_file = os.path.join(directory, "environ")
+        if not os.path.isfile(environ_file):
+            continue
+        uid = os.stat(environ_file).st_uid
+
+        # The following line assumes that user accounts start at 1000 and that
+        # no one works using the root or another system account. This is rather
+        # restrictive, but de facto default. Alternatives would be to use the
+        # UID_MIN from /etc/login.defs or FIRST_UID from /etc/adduser.conf;
+        # but effectively, both values aren't binding in any way.
+        # If this breaks your use case, please file a bug on Github.
+        if uid < 1000:
+            continue
+
+        process_environ = {}
+        for environ_entry in open(environ_file).read().split("\0"):
+            if "=" in environ_entry:
+                name, value = environ_entry.split("=", 1)
+                if name == "DISPLAY" and "." in value:
+                    value = value[:value.find(".")]
+                process_environ[name] = value
+
+        if "DISPLAY" not in process_environ:
+            # Cannot work with this environment, skip.
+            continue
+
+        # To allow scripts to detect batch invocation (especially useful for predetect)
+        process_environ["AUTORANDR_BATCH_PID"] = str(os.getpid())
+        process_environ["UID"] = str(uid)
+
+        display = process_environ["DISPLAY"]
+
+        if "XAUTHORITY" not in process_environ:
+            # It's very likely that we cannot work with this environment either,
+            # but keep it as a backup just in case we don't find anything else.
+            backup_candidates[display] = process_environ
+            continue
+
+        if display not in X11_displays_done:
+            try:
+                pwent = pwd.getpwuid(uid)
+            except KeyError:
+                # User has no pwd entry
+                continue
+
+            fork_child_autorandr(pwent, process_environ)
+            X11_displays_done.add(display)
+
+    # Run autorandr for any users/displays which didn't have a process with
+    # XAUTHORITY set.
+    for display, process_environ in backup_candidates.items():
+        if display not in X11_displays_done:
+            try:
+                pwent = pwd.getpwuid(int(process_environ["UID"]))
+            except KeyError:
+                # User has no pwd entry
+                continue
+
+            fork_child_autorandr(pwent, process_environ)
+            X11_displays_done.add(display)
+
 
 def main(argv):
     try:
-       options = dict(getopt.getopt(argv[1:], "s:l:d:cfh", [ "dry-run", "change", "default=", "save=", "load=", "force", "fingerprint", "config", "help" ])[0])
+        opts, args = getopt.getopt(argv[1:], "s:r:l:d:cfh", ["batch", "dry-run", "change", "default=", "save=", "remove=", "load=", "force", "fingerprint", "config", "debug", "skip-options=", "help"])
     except getopt.GetoptError as e:
-        print(str(e))
-        options = { "--help": True }
+        print("Failed to parse options: {0}.\n"
+              "Use --help to get usage information.".format(str(e)),
+              file=sys.stderr)
+        sys.exit(posix.EX_USAGE)
 
-    profile_path = os.path.expanduser("~/.autorandr")
+    options = dict(opts)
 
-    try:
-        profiles = load_profiles(profile_path)
-    except Exception as e:
-        print("Failed to load profiles:\n%s" % str(e), file=sys.stderr)
-        sys.exit(1)
+    if "-h" in options or "--help" in options:
+        exit_help()
 
+    # Batch mode
+    if "--batch" in options:
+        if ("DISPLAY" not in os.environ or not os.environ["DISPLAY"]) and os.getuid() == 0:
+            dispatch_call_to_sessions([x for x in argv if x != "--batch"])
+        else:
+            print("--batch mode can only be used by root and if $DISPLAY is unset")
+        return
+    if "AUTORANDR_BATCH_PID" in os.environ:
+        user = pwd.getpwuid(os.getuid())
+        user = user.pw_name if user else "#%d" % os.getuid()
+        print("autorandr running as user %s (started from batch instance)" % user)
+
+    profiles = {}
+    profile_symlinks = {}
     try:
-        config, modes = parse_xrandr_output()
+        # Load profiles from each XDG config directory
+        # The XDG spec says that earlier entries should take precedence, so reverse the order
+        for directory in reversed(os.environ.get("XDG_CONFIG_DIRS", "/etc/xdg").split(":")):
+            system_profile_path = os.path.join(directory, "autorandr")
+            if os.path.isdir(system_profile_path):
+                profiles.update(load_profiles(system_profile_path))
+                profile_symlinks.update(get_symlinks(system_profile_path))
+        # For the user's profiles, prefer the legacy ~/.autorandr if it already exists
+        # profile_path is also used later on to store configurations
+        profile_path = os.path.expanduser("~/.autorandr")
+        if not os.path.isdir(profile_path):
+            # Elsewise, follow the XDG specification
+            profile_path = os.path.join(os.environ.get("XDG_CONFIG_HOME", os.path.expanduser("~/.config")), "autorandr")
+        if os.path.isdir(profile_path):
+            profiles.update(load_profiles(profile_path))
+            profile_symlinks.update(get_symlinks(profile_path))
+        # Sort by descending mtime
+        profiles = OrderedDict(sorted(profiles.items(), key=lambda x: -x[1]["config-mtime"]))
     except Exception as e:
-        print("Failed to parse current configuration from XRandR:\n%s" % str(e), file=sys.stderr)
-        sys.exit(1)
+        raise AutorandrException("Failed to load profiles", e)
+
+    profile_symlinks = {k: v for k, v in profile_symlinks.items() if v in (x[0] for x in virtual_profiles) or v in profiles}
+
+    exec_scripts(None, "predetect")
+    config, modes = parse_xrandr_output()
 
     if "--fingerprint" in options:
         output_setup(config, sys.stdout)
@@ -491,41 +1016,90 @@ def main(argv):
         output_configuration(config, sys.stdout)
         sys.exit(0)
 
+    if "--skip-options" in options:
+        skip_options = [y[2:] if y[:2] == "--" else y for y in (x.strip() for x in options["--skip-options"].split(","))]
+        for profile in profiles.values():
+            for output in profile["config"].values():
+                output.set_ignored_options(skip_options)
+        for output in config.values():
+            output.set_ignored_options(skip_options)
+
     if "-s" in options:
         options["--save"] = options["-s"]
     if "--save" in options:
-        if options["--save"] in ( x[0] for x in virtual_profiles ):
-            print("Cannot save current configuration as profile '%s':\nThis configuration name is a reserved virtual configuration." % options["--save"])
-            sys.exit(1)
+        if options["--save"] in (x[0] for x in virtual_profiles):
+            raise AutorandrException("Cannot save current configuration as profile '%s':\nThis configuration name is a reserved virtual configuration." % options["--save"])
         try:
-            save_configuration(os.path.join(profile_path, options["--save"]), config)
+            profile_folder = os.path.join(profile_path, options["--save"])
+            save_configuration(profile_folder, config)
+            exec_scripts(profile_folder, "postsave", {"CURRENT_PROFILE": options["--save"], "PROFILE_FOLDER": profile_folder})
         except Exception as e:
-            print("Failed to save current configuration as profile '%s':\n%s" % (options["--save"], str(e)), file=sys.stderr)
-            sys.exit(1)
+            raise AutorandrException("Failed to save current configuration as profile '%s'" % (options["--save"],), e)
         print("Saved current configuration as profile '%s'" % options["--save"])
         sys.exit(0)
 
-    if "-h" in options or "--help" in options:
-        exit_help()
+    if "-r" in options:
+        options["--remove"] = options["-r"]
+    if "--remove" in options:
+        if options["--remove"] in (x[0] for x in virtual_profiles):
+            raise AutorandrException("Cannot remove profile '%s':\nThis configuration name is a reserved virtual configuration." % options["--remove"])
+        if options["--remove"] not in profiles.keys():
+            raise AutorandrException("Cannot remove profile '%s':\nThis profile does not exist." % options["--remove"])
+        try:
+            remove = True
+            profile_folder = os.path.join(profile_path, options["--remove"])
+            profile_dirlist = os.listdir(profile_folder)
+            profile_dirlist.remove("config")
+            profile_dirlist.remove("setup")
+            if profile_dirlist:
+                print("Profile folder '%s' contains the following additional files:\n---\n%s\n---" % (options["--remove"], "\n".join(profile_dirlist)))
+                response = input("Do you really want to remove profile '%s'? If so, type 'yes': " % options["--remove"]).strip()
+                if response != "yes":
+                    remove = False
+            if remove is True:
+                shutil.rmtree(profile_folder)
+                print("Removed profile '%s'" % options["--remove"])
+            else:
+                print("Profile '%s' was not removed" % options["--remove"])
+        except Exception as e:
+            raise AutorandrException("Failed to remove profile '%s'" % (options["--remove"],), e)
+        sys.exit(0)
 
-    detected_profile = find_profile(config, profiles)
+    detected_profiles = find_profiles(config, profiles)
     load_profile = False
 
     if "-l" in options:
         options["--load"] = options["-l"]
     if "--load" in options:
         load_profile = options["--load"]
+    elif len(args) == 1:
+        load_profile = args[0]
     else:
+        # Find the active profile(s) first, for the block script (See #42)
+        current_profiles = []
         for profile_name in profiles.keys():
-            if profile_blocked(os.path.join(profile_path, profile_name)):
-                print("%s (blocked)" % profile_name)
+            configs_are_equal = is_equal_configuration(config, profiles[profile_name]["config"])
+            if configs_are_equal:
+                current_profiles.append(profile_name)
+        block_script_metadata = {
+            "CURRENT_PROFILE": "".join(current_profiles[:1]),
+            "CURRENT_PROFILES": ":".join(current_profiles)
+        }
+
+        for profile_name in profiles.keys():
+            if profile_blocked(os.path.join(profile_path, profile_name), block_script_metadata):
+                print("%s (blocked)" % profile_name, file=sys.stderr)
                 continue
-            if detected_profile == profile_name:
-                print("%s (detected)" % profile_name)
-                if "-c" in options or "--change" in options:
-                    load_profile = detected_profile
-            else:
-                print(profile_name)
+            props = []
+            if profile_name in detected_profiles:
+                props.append("(detected)")
+                if ("-c" in options or "--change" in options) and not load_profile:
+                    load_profile = profile_name
+            if profile_name in current_profiles:
+                props.append("(current)")
+            print("%s%s%s" % (profile_name, " " if props else "", " ".join(props)), file=sys.stderr)
+            if not configs_are_equal and "--debug" in options and profile_name in detected_profiles:
+                print_profile_differences(config, profiles[profile_name]["config"])
 
     if "-d" in options:
         options["--default"] = options["-d"]
@@ -533,35 +1107,75 @@ def main(argv):
         load_profile = options["--default"]
 
     if load_profile:
-        if load_profile in ( x[0] for x in virtual_profiles ):
-            profile = generate_virtual_profile(config, modes, load_profile)
+        if load_profile in profile_symlinks:
+            if "--debug" in options:
+                print("'%s' symlinked to '%s'" % (load_profile, profile_symlinks[load_profile]))
+            load_profile = profile_symlinks[load_profile]
+
+        if load_profile in (x[0] for x in virtual_profiles):
+            load_config = generate_virtual_profile(config, modes, load_profile)
+            scripts_path = os.path.join(profile_path, load_profile)
         else:
             try:
                 profile = profiles[load_profile]
+                load_config = profile["config"]
+                scripts_path = profile["path"]
             except KeyError:
-                print("Failed to load profile '%s':\nProfile not found" % load_profile, file=sys.stderr)
-                sys.exit(1)
-        add_unused_outputs(config, profile)
-        if profile == config and not "-f" in options and not "--force" in options:
-            print("Config already loaded")
+                raise AutorandrException("Failed to load profile '%s': Profile not found" % load_profile)
+            if load_profile in detected_profiles and detected_profiles[0] != load_profile:
+                update_mtime(os.path.join(scripts_path, "config"))
+        add_unused_outputs(config, load_config)
+        if load_config == dict(config) and "-f" not in options and "--force" not in options:
+            print("Config already loaded", file=sys.stderr)
             sys.exit(0)
+        if "--debug" in options and load_config != dict(config):
+            print("Loading profile '%s'" % load_profile)
+            print_profile_differences(config, load_config)
+
+        remove_irrelevant_outputs(config, load_config)
 
         try:
             if "--dry-run" in options:
-                apply_configuration(profile, True)
+                apply_configuration(load_config, config, True)
             else:
-                exec_scripts(os.path.join(profile_path, load_profile), "preswitch")
-                apply_configuration(profile, False)
-                exec_scripts(os.path.join(profile_path, load_profile), "postswitch")
+                script_metadata = {
+                    "CURRENT_PROFILE": load_profile,
+                    "PROFILE_FOLDER": scripts_path,
+                }
+                exec_scripts(scripts_path, "preswitch", script_metadata)
+                if "--debug" in options:
+                    print("Going to run:")
+                    apply_configuration(load_config, config, True)
+                apply_configuration(load_config, config, False)
+                exec_scripts(scripts_path, "postswitch", script_metadata)
+        except AutorandrException as e:
+            raise AutorandrException("Failed to apply profile '%s'" % load_profile, e, e.report_bug)
         except Exception as e:
-            print("Failed to apply profile '%s':\n%s" % (load_profile, str(e)), file=sys.stderr)
-            sys.exit(1)
+            raise AutorandrException("Failed to apply profile '%s'" % load_profile, e, True)
+
+        if "--dry-run" not in options and "--debug" in options:
+            new_config, _ = parse_xrandr_output()
+            if not is_equal_configuration(new_config, load_config):
+                print("The configuration change did not go as expected:")
+                print_profile_differences(new_config, load_config)
 
     sys.exit(0)
 
-if __name__ == '__main__':
+
+def exception_handled_main(argv=sys.argv):
     try:
         main(sys.argv)
-    except Exception as e:
-        print("General failure. Please report this as a bug:\n%s" % (str(e),), file=sys.stderr)
+    except AutorandrException as e:
+        print(e, file=sys.stderr)
         sys.exit(1)
+    except Exception as e:
+        if not len(str(e)):  # BdbQuit
+            print("Exception: {0}".format(e.__class__.__name__))
+            sys.exit(2)
+
+        print("Unhandled exception ({0}). Please report this as a bug at https://github.com/phillipberndt/autorandr/issues.".format(e), file=sys.stderr)
+        raise
+
+
+if __name__ == '__main__':
+    exception_handled_main()